Part 69817 (often seen as 69817-1) is a genuine OEM plug-in headlight wiring harness designed for Western and Fisher snowplows. It's specifically made for newer GM trucks that use HB3, H11, or HIR2 headlight bulbs and are equipped with a 3-port isolation module for the plow's electrical system. This harness ensures proper electrical connection and lighting functionality between the truck and the snowplow.